Noting that the press has largely turned its resources off of the Fukushima complex, and needing up-to-date information on the status of the damage control efforts there, we secured the most up-to-date satellite photo from DigitalGlobe (dated March 31st), which we analyze below. This is the first photo of the damaged reactor site at Japan's Fukushima Dai-ichi nuclear facility made available to the public in over a week. That means you, our readers, are the first public eyes anywhere to see this photo.

Drawing upon the expertise of our resident nuclear engineer and Ann Stringer, imaging expert, we conclude that the situation at Fukushima is not stabilized: Things are not yet at a place of steady progress in the containment and clean-up efforts. It's still a dance, forwards and backwards, with the workers making gains here and there but the situation forcing them to react defensively all too often.

In this report, we will tell you what we know for sure, what we are nearly certain of, and what we remain forced to speculate about.

Here is a portion of a much larger image (covering 25 square kilometers in total) showing the reactor complex as of March 31, at roughly mid-day:

Photo Credit, 2011, DigitalGlobe

What We Can See

Here's what we can directly observe in the larger satellite image:

Steam is still rising from Reactors #2, #3 (circled in green), and #4.

Of the four reactor buildings, three are nearly or totally destroyed, while the outside (at least) of the fourth is in relatively better shape.

We can count 7 fire trucks 'on site' with another 7 just to the north, all with water lines strung out across the ground.

There is only one ship/vessel to be seen, located inside of the breakwater and nearly as far to the north as it can go inside that boundary.

A significant number of the vehicles that can be seen at the core of the site have not moved since the first released photos on March 12.

There is a parking lot slightly to the north and west with approximately 250 passenger vehicles in it and a side lot with 30 large green tanks neatly arranged in rows.

The rest of the area contains one-, two-, and four-lane roads (no traffic at all), worked farmland, residential and commercial areas, mostly empty parking lots, and two baseball diamonds.

Here's what we don't see...

Nowhere in the 25 km area in the main photo can we find anything that looks like a staging area with a large collection of assets such as tanker trucks, pumpers, cement trucks, piles of pre-staged materials, ambulances, and fire trucks.

The cement pumper truck seen a week ago has been apparently replaced by the boom at Reactor #4.

There's no obvious barge delivering fresh water for the reactor cooling efforts as recently reported. (Perhaps it has come and gone?)

There are no obvious changes to the roofs of any of the reactors.

We don't see any people outside the plants working.

Things we can logically conclude...

The steam that is venting is a mixed blessing. It implies that cooling water is getting to some hot material, which is a good thing, but it also means that something is hot enough to vaporize water, leading to the continued release of radioactive contamination into the surrounding environment and further bombarding the reactor complex with radiation, which complicates the work efforts. [Note: prior sentence edited for clarity on April 2, 2011].

This means that the lack of steam coming from Reactor #1 is either a very good sign, or a very bad sign. Good because it could mean that the containment vessels are intact and cooling water is circulating. Bad because it could imply that no water is getting to it, and it is a very hot mass right now. According to TEPCO, Reactor #1 has had seawater, and now freshwater, circulating through the reactor vessel - and since both containment vessels are intact, we'll conclude the lack of steam is a good sign.

The situation at Fukushima is going to drag on for years. First there's the matter of stabilizing the situation, and this has not yet been fully achieved. Recent surprises in terms of the amounts and locations of radioactivity are one sign that the situation is not fully stabilized. Still, nothing has blown up in quite a while, the steam venting appears consistent, and the major surprises seem to be over for now. While the TEPCO workers are still reacting to things as they arise, these are smaller issues than last week, which is another hopeful sign.

The detected presence of neutron beams, I-134, and radioactive chlorine are all strongly supportive of the idea that criticality has resumed. Our best guess is that these are localized pockets, probably of short duration, and do not involve the entire core mass of any particular reactor conflagrating in some gigantic, greenish blob of uncontrolled fission. The geometries of the fuel in relation to neutron moderators requires precise conditions to support sustained fission and so it is rather unlikely to be occurring in anything other than localized pockets. If the entire reactor in its fully operational state was capable of supporting what we might scale to 100% fission, the amount of fission happening after a partial (or complete) meltdown will be a far lesser percentage. Still, any amount of fission is unwelcome at this point, because it is adding to the heat and generating fresh radioactive elements that can escape.

The constantly rising levels of radioactivity found in the seawater are a further unwelcome development, but without a proper isotope analysis, we cannot conclude anything about the potential resumption of fission from their gross amounts alone. It's always possible that the leftover fission products are now being washed in larger amounts into the sea for some reason.

Additional Drone Photos

These are the most detailed photos yet to emerge into the public space (released yesterday, March 31, as far as I know), and they are purported to come from a drone flyover on March 20 and 24. They are really quite good, and worth viewing in their entirety here.

Beginning with Reactor #3, one thing we can say is that this thing is a right proper mess:

There's a significant hole to the left of center that goes deep into the sub-structure (with a strange greenish cast that we've not been able to resolve after much conjecture) and it's clear that this building alone will take a long time to resolve.

Interestingly, we get our clearest image yet of the hole in turbine building #3 that was created by something ejected into the air during the Reactor #3 explosion.

Looking like one of those cartoon cutouts that happens when the coyote hits the ground, we get the impression that whatever it was happened to be quite heavy and possibly shaped like an Apollo capsule. It has been my suspicion, contradicting the official story, that the concrete containment vessel was what actually blew up in Reactor #3. I have been looking for evidence of in the form of large, heavy chunks of concrete (especially the refueling plug) lying about. I don't know what made this hole in the roof of the turbine building, but it was heavy.

Reactor #4 provides us with proof that serious damage can result from the effects of an overheated spent fuel storage pool:

Here the watering boom can be clearly seen. A camera was recently attached to the boom, and it took some interior shots that were suggestive of the idea that the spent fuel pool is damaged and largely drained of water. Spraying water into this pool, then, is probably a balancing act, with the desire to spray enough water on the rods to keep them cool being offset by the risk of having radioactive water drain away for parts unknown.

Almost certainly this same balancing act defines the efforts for Reactors #2 and #3 as well.

Conclusions

The efforts at Fukushima are probably weeks away from even basic stabilization, and we are years away from any sort of a final resolution. This crisis is going to be with all of us for a very long time. Radioactive material will continue to escape from the complex into the environment for weeks at best, and months or years at worst.

The chief concern here is that things might still take a turn for the worse, whereby radiation spikes to levels that prevent humans from getting close enough to perform meaningful operations and work on the site. If the radiation spikes high enough, it will force an evacuation from the vicinity, complicating every part of what has to happen next, from monitoring to remediation.

The general lack of staged materials anywhere in the vicinity indicates that authorities have not yet decided on a plan of action, feeding our assessment that they are still in 'react mode' and that we are weeks away from nominal stabilization.

On Thursday we learned from the Wall Street Journal that TEPCO only had one stretcher, a satellite phone, 50 protective suits, and enough dosimeters to give only a single one to each worker group. Given this woeful level of preparation, it is not surprising to see that regular fire trucks, cement trucks, and a lack of staged materials comprise much of the current damage-control mix.

We don't yet know enough to conclude how much fission has spontaneously re-occurred, but we have strong suspicions that the number is higher than zero. Here we make our call for the release of more complete and timely radiation readouts and sampling results by TEPCO and Japan so that we can assess what the true risks are. The situation remains fluid, and quite a lot depends now on chance and which way the wind blows.

And as I detailed in the Alert report I issued soon after the tragic events of the Japan earthquake and tsunami on March 10, the impact of Japan's tribulations on the global economy will be large and vast. World markets are simply unprepared for the third-largest economy to suddenly and violently downshift. The persisting crisis at Fukushima simply worsens the picture.

As always, we'll continue montioring developments closely and reporting our findings and conclusions on this site.

Join the discussion

50 Comments

Very informative, non-sensationalized, report. Hard to find these days.

We (my wife and I) subscribe to NHK and my wife told me that on the news tonight (April 2nd, morning in Japan) the Japanese Gov't was considering asking the U.S. Navy to dispose of radioactive waste water and this was considered one of the big issues they were pondering. My wife is native Japanese (now U.S. citizen) so the translation is good. Not much more detail though.

This was a very in depth report which lends support to the idea that this crisis will be with us for some time. I think it is really sad that the situation in Japan is barely mentioned on some news broadcasts.

As dreadful as the nuclear situation is, it was helpful to hear CM reference his alert from a few weeks ago. If you listen to the mainstream press you would think the economy is popping along and the only place the global markets can go is up.

It's well worth watching the video in the link because you will get a feel for just how messy the situation is by watching people on a windy day taking readings, getting in and out of a vehicle, pulling their masks on and off, and generally being forced to accept some level of contamination along the way.

There's just no way to stop something you can't see from getting all over everything.

That is a very informative analysis. A few days ago we saw reports comparing the amount of contamination from Fukushima to Chernobyl. It was still lower at that time, but high, and Fukushima is expected to continue creating contamination for a longer period of time, probably much longer as you report. The likely results would be a higher total amount of contamination than Chernobyl.

Since Fukushima did not have an active core directly exposed, and a raging fire, it seems contamination was not drawn into the upper atmosphere and the jet streams, like Chernobyl. Yet if the total amount of contamination over time is larger, this bodes very badly for Japan and its neighbors. Your map of unlivable areas around Chernobyl compared to Japan was instructive. Japan can’t afford to have a significant area become uninhabitable. I would appreciate any thoughts the CM team, or members, may have on the likelihood of Fukushima creating more total contamination.

As far as effect on the world economy does, I have heard somewhat cynical assessment that Japan's trouble is good for the US. The logic goes - this is destruction of productive capacity, likely to increase US market share and allow some firms to raise prices. Rebuild effort is likely to lead to increased orders from the US, too. Plus central banks are going to be more accomodating, preventing any debt or foreign exchange disruptions. Sure, some companies may also suffer due to supply chain disruption, but these effects are likely to be dwarfed.

One comment: one of the things the mainstream media has done so very poorly in regard to this story is to blindly repeat government assurances that 'levels of radiation' pose no 'no immediate threat' - and the way in which this tends to be done is by confusing, through intention or ignorance, the terms 'radioactivity' and 'radiation' - it's a tip off that the report either 1) doesn't know what its talking about (usually, a journalist), or 2) is engaged in misinformation (typically, a government official or member of the nuclear lobby).

Unfortunately, the analysis above falls prey to the same confusion, when it states:

"Radiation will continue to escape from the complex into the environment"

It's not radiation escaping that is the problem - its escaping radioactivity and the attendant contamination.

Radiation would be alpha and beta particles, and gamma waves. These are dangerous to the 'Fukushima 50' or others exposed to them, but not to the world at large. The serious health threat here is radioactive materials escaping (isotopes of iodine, cesium, etc). Those materials, carried in wind currents and in earth and sea, get ingested by living things (e.g. humans and fish and asparagus), and accumulate, and can then be ingested by other living things which eat them (think: food web).

Here's the key point which you will not have grasped from reading the mainstream media: the danger lies with these 'internal emitters' - that is, isotopes which are ingested (breathed in or eaten). That is what will cause cancers worldwide. That is what gives this crisis global scope. NOT radiation (alpha, beta, gamma) emanating from the plant.

So from the standpoint of global public health (and remember: scientists insist that residue from Chernobyl continues to this day to cause new cases of thyroid cancer, years after the isotopes themselves have degraded to harmlessness), the statement should have read:

"Radioactivity [or radioisotopes] will continue to escape from the complex into the environment"

With this understanding, it is worth noting that such isotopes have in fact already been detected on both the east and west coasts of America, so we can safely assume that if they've reached the heartland by now or will very soon. The only effective 'defense' I know of - and a very partial, limited one at that - is to increase uptake of iodine via kelp or supplement of some form. At least, this may protect from iodine-131, which tends to lodge in the thyroid and leads to thyroid cancer years later. As the wikipedia page on I-131 puts it:

"Much smaller incidental doses of iodine-131 than are used in medical treatment, are thought to be the major cause of increased thyroid cancers after accidental nuclear contamination. These cancers happen from residual tissue radiation damage caused by the I-131, and usually appear years after exposure, long after the I-131 has decayed."

As far as effect on the world economy does, I have heard somewhat cynical assessment that Japan's trouble is good for the US. The logic goes - this is destruction of productive capacity, likely to increase US market share and allow some firms to raise prices. Rebuild effort is likely to lead to increased orders from the US, too. Plus central banks are going to be more accomodating, preventing any debt or foreign exchange disruptions. Sure, some companies may also suffer due to supply chain disruption, but these effects are likely to be dwarfed.

What is your take on this?

Companies will step in to make monies off of the disaster. And as you say, foreign firms will benefit from the Japan disruption in that they will have lost some competition and gained access to new markets.

Another thought is that even Japanese firms will benefit from rebuilding their own infrastructure.

To me these short term outcomes are just mini bubbles of the kind that are created all the time.

The bigger and more important issue for all of us is that the destruction of infrastructures simply put additional pressures on scarse commodities and increase debt. As such the quake is ultimately destructive for the world economy as a whole.

I would appreciate any thoughts the CM team, or members, may have on the likelihood of Fukushima creating more total contamination.

Travlin

It all depends, but "Jim in MN" over at ZH has taken a solid swipe at the data:

First, the scale of the situation:

Oak Ridge National Laboratory analyzed the core constituents at the Brown's Ferry nuclear plant as a 'reference unit' for boiling water reactors. In a 1,065 MW core, cesium was estimated at 429 kg given an extended period of fuel irradiation.

For the slightly smaller 1,000 MW Chernobyl core the comparable figure would be 402 kg if the fuel was fully irradiated, but Chernobyl Unit 4 was only three years old. For the Fukushima Daiichi Units 2, 3 and 4 rated at 784 MW, 315 kg of cesium should be present in each core load of fuel. For the 460 MW Unit 1 185 kg of cesium would be present.

Thus, in the cores of Units 1-4, some 1,130 kg of cesium was in place when the accident occurred. Adding the spent fuel pools (net of the offloaded Unit 4 core) gives an additional 1,245 kg for a total of 2,375 kg of cesium in the damaged buildings.

3 of 3 (no air dispersal analysis yet; will work on it)

Fraction Of On-Site Material Emitted Into the Atmosphere

According to the UN, only 22 kg of cesium was released into the atmosphere as a result of the Chernobyl accident. The amount of cesium at the Fukushima Daiichi site, then, represents over 100 Chernobyl releases. The next question is, what fraction of the total cesium may be released into the atmosphere from Fukushima Daiichi?

The potential amount of Cesium is 100x what got released at Chernobyl. That's the maximum and a far, far smaller fraction than that will be eventually released, but that gives us an idea of the scale involved.

The longer the reactors and spent fuel pools can vent, leak, drip, and otherwise eject their contents into the environment, the worse the release amounts will be.

So nobody knows at this point how much will be released, but Japan has been incredibly lucky in one regard, the winds have been nearly perfectly steady off-shore patterns since the start of the crisis. even with this, the few circulating wind patterns that have briefly existed have been sufficient to render towns 40 km away (mainly to the north so far, again luckily from a population density standpoint) as worthy of immediate evacuation, at least by some international standards.

"Radioactivity [or radioisotopes] will continue to escape from the complex into the environment"

Good catch. I am normally quite clear on the difference between radiation and contamination and I left out the contamination part. There was quite a race on yesterday to rapidly analyze the images, decice what we could say and not say, get it all written up, while trying to balance speed with accuracy. Overall we did a pretty good job, and it was a team effort I should stress, but the final responsibility for the writing is mine.

I am, actually, concerned about radiation itself because if it climbs high enough it will prevent effective work from being performed at the plant. And I am also concerned about radioactive contamination. I should have had both in there.

So I would amend your line to read, "Radioactivity [or radioisotopes] will continue to escape from the complex into the environment and radiation will continue to bombard the reactor work environment."

One comment: one of the things the mainstream media has done so very poorly in regard to this story is to blindly repeat government assurances that 'levels of radiation' pose no 'no immediate threat' - and the way in which this tends to be done is by confusing, through intention or ignorance, the terms 'radioactivity' and 'radiation' - it's a tip off that the report either 1) doesn't know what its talking about (usually, a journalist), or 2) is engaged in misinformation (typically, a government official or member of the nuclear lobby).

ozzy -

Good catch. You forgot to mention option 3) contains a typo.

PM sent requesting correction - thanks for the backup. Talk about defense in depth...

Consensus at this point is that this is a minor temporary supply chain problem for a few things like autos & semiconductors, & that this could prove positive for production in the US & other countries. There are truths to these arguments & they may prove accurate, but they are too simplistic & linear for my taste, when the effects of this are likely to be nonlinear.

The big question is how big & where will the exclusion zone from this accident ultimately be. Reason being that i've seen estimates that 25-30% or more of Japan's GDP is in Tokyo. If Tokyo becomes unlivable, now we have problems for the Japanese economy, currency & global financial system. I do know there is for example a Hitachi plant that makes air flow regulators for 60% of the world's cars that is out of commission; the other 40% are made in Europe, by Bosch apparently. They will ramp up at some point, but if this plant is too close to Fukushima, it is not coming back on line for decades...so you are looking at disruption to 60% of the autos produced in the world, for whatever period of time it takes to expand global air flow regulator capacity by 60%. In the mean time, does this ripple thru to steel producers, auto dealers, industrial companies, etc. the world over. Still unknowable.

Also consider that when Lehman Bros went under, it had an $800B balance sheet, plus derivatives. Japan's GDP is $5T, they have $10T of gov't debt outstanding (JGB's), plus own $880B or so of US Treasuries - to say nothing of the currency positions held out there, the size of the Yen carry trade whereby the financial world is massively short the yen as a cheap funding mechanism. Further, a significant chunk of the JGB's are held by Japanese corporations.

Japan is the most levered nation in the world - they MUST have a trade surplus to fund that. I think the world currency & bond markets will give them a pass for as long as those markets believe the optimistic, consensus case that Japan will rebuild. If it becomes apparent that a significant chunk of Northern Japan &/or Tokyo will become uninhabitable exclusion zones for the next 50+ years, you could see all hell break loose, given the amounts I cited above.

The yen could collapse, as the productive capacity supporting it would be uninhabitable. This would conceivable upset global trade as the Japanese could theoretically land a Lexus in the US for cheaper than a Ford Fusion, IF they could afford the iron ore, met coal & oil needed to produce those cars...which they might want to use the $800B in Treasuries to buy...but then again, remember many of the JGB's are held by Japanese corporations & banks; if the yen collapsed, JGB values would collapse, & suddenly you would have massive holes in the balance sheets of Japanese corporations.

Alternatively, if they are unable to afford raw materials b/c of the collapse of the yen, the value of those $10T in JGB's would also collapse, leaving massive holes in Japanese corporate balance sheets, which would have ripple effects through the financial markets that are unknowable, but likely to be not good, & ultimately quite inflationary, as either money is printed by authorities to help the system, or currency values are undermined.

I don't think this provides "the answer" to your question, but hopefully it will help you with what some of the "right questions" to ask are. I think the fact that in the 1st week after the earthquake, the BOJ injected $450B into their markets, combined with $10s of billions more injected by global central banks to intervene in the yen markets, gives some idea of magnitude of how big the problem could be in the financial markets & economy (a $450B injection in 4 days by the BOJ would be like the US Fed injecting $1.5T, or 2x the size of TARP, in less than a week.)

Hi Chris, Great summation of events. Question: You mentioned the lack of a staging area at or around the Fukushima Nuclear Plant. As you probably know by now, news is reporting that workers have been sequestered to an area 20 km away from the site - called J camp. Have you been able to locate a satellite photo of the area? It should provide an indication of how well the organizational efforts are progressing. TIA.

And no matter the problems around the world, the us stock market keeps going up. How can no news organization not question this? The FED is running out of bullets. If Japan must sell a significant chunk of US t-bills, then the FED is not ending QE in June. But how can it sop up t-bills being put in the secondary market at higher price than others will be willling to pay? We could see inflation really take off this summer. We need a state to secede and we all can move there.

I would appreciate any thoughts the CM team, or members, may have on the likelihood of Fukushima creating more total contamination.

<Excerpt>

The potential amount of Cesium is 100x what got released at Chernobyl. That's the maximum and a far, far smaller fraction than that will be eventually released, but that gives us an idea of the scale involved.

Thanks for the helpful response Chris. This confirms my thoughts that Fukushima has the potential to exceed Chernobyl in total contamination. Even though news reports still picture it as not nearly so bad, it is rapidly approaching that measure. The effects on a dense population confined to a largely mountainous island would be even more severe.

What I see missing even from reports like yours is any mention of what happens if there is another quake here, even if it's smaller. It seems everyone is ignoring this as an issue and speculatiing on how long it will take to repair the present damage. Another quake and resulting wave would completely destroy what's left.

In additon, it seems that ESA has just released a report that shows a large portion of the eastern part of Japan sliding eastward towards a 20,000' drop off. Some reports already suggest that one more big quake in the area would damage the already unstable and weakened land mass sending at least the area with the power plants into the Japan Trench which runs for almost 500 miles along the eastern side of the island.

The upside to such an event? The extreme depths would probably allow the ocean to subdue the radioactivity enough to prevent it from poisoning the air above Japan and the water around it for 1,000 of years.

What I see missing even from reports like yours is any mention of what happens if there is another quake here, even if it's smaller. It seems everyone is ignoring this as an issue and speculatiing on how long it will take to repair the present damage. Another quake and resulting wave would completely destroy what's left.

Excellent job as always Chris. So good, in fact, that somehow you seem to have got the attention of the normally oblivious (or willfully ignorant) MSM. I was flipping through the news channels, and I stopped on Fox news when I saw satellite photos of the nuclear plant site. They looked awfully familiar, and sure enough they were using your first photo above, citing PeakProsperity.com and digital globe. From what little I caught I didn't hear them cite or paraphrase any of this or previous blog posts (they mostly were talking about possibilities of entombment), but they had the photo up for the majority of the segment. So far I haven't seen the same on their website though, only on their cable channel. (edit: it looks like they're also showing photo#5 a lot, the close up photo of the hole, as well and citing this site)

So on the plus side, this means that apparently some MSM is following your work. On the bad side, so far I've seen no discussion of ANY of the broader implications that you have been pointing out these last few weeks, which pushes me to more to the conclusion that their under-reporting is intentional.

The PDF is well worth your time, even if you are not into the details. It's really cool to scroll through it quickly and watch the picture of the plant change ... it really gives you a perspective on what may have been happening and how it progressed.

Everything that I have read about this situation just resounds with the most astounding incompetence, again and again.

We hear these lame stories about how a team is reconnecting the power, 10 days after the first outage. We hear stories about Tepco ordering spare parts for the damaged pumps two weeks after the accident.

Any kind of basic management seems to be totally lacking. The first thing that anyone would think of, day one, after such an accident is reconnecting the power and ordering in spare pumps in case the ones onsite are damaged. Its just incredible the lax efforts that were made in the days after the accident.

What is also worse is this Asian problem of "saving face". OK the same thing went on to some extent with the BP disaster, but at one point, they just came clean and gave everyone the info. The Japanese have been terrible in this regard, and any respect I have for the nation has evaporated. I think even the Chinese with all the politics and communism, would have been more upfront about a disaster of this scale. Its really sickening, the dicking about that has gone on on the japanese side. This disaster effects the whole world and they have not responded properly, sent in low grade workers without proper protection and not thought of things that anyone on the internet reading the story can clearly comprehend as being the first most important steps to take.

Another waffling perma bear that can think of only worst case scenarios.

How about this :

Fukashima is not the next chernobyl, far from it, chernobyl blew up over night with no warning, Fukasima is only a small leakage problem, far from a meltdown and will be contained with only minor real leakage.

Japan is not yet suffering power outages, and will survive ok, no developed country like Japan can rely on 100% capacity for its power generation. It will be ok, and the japanese of all cultures are very resiliant and resourceful.

The markets breath a sy of relief as Libya is contained and other gulf states trouble calms down.

Gold comes off in price as its already doing.

Oil comes off in price as its already doing.

Life goes on and the perma bears that are constantly predicting the end of the world get to look pretty daft hiding away in the woods with the depreciating gold and hords of firearms... .

see ya guys.....

[Moderator's note: While the viewpoint is welcome, the strident tone is not appropriate. Comments must be phrased in a fact-based, informative, and constructive manner. Corrective action with the user has been undertaken.]

"The end of Configuration 1 has been defined as the decay time that is necessary to ensure that the fuel rod cladding remains intact given a loss of all spent fuel pool water. The previous study7 defined 650°C as a maximum temperature for cladding integrity. The Workshop on Transportation Accident Scenarios 47 estimated incipient clad failure at 565°C with expected failure at 671"C, presumably based on expert opinion. Given that the large seismic event is the dominant contributor to the configuration 1initiator, it is likely that it would take a prolonged period of time to retrieve the fuel, repair the spent fuel pool or establish an alternate means of long-term spent fuel storage. Therefore, we presume there will be a significant period of time that the fuel will be exposed to air. On this basis, BNL has chosen a temperature of 565°C as the critical cladding temperature.

This results in critical decay times of about 17 months for the representative PWR and 7 months for the representative BWR "

If I interpret that correctly, it means about 2% ( 7 months / 40 years) of the spent rods are likely to break down in a dry pool situation...

"The core melt accident results are provided for two emergency protective actions:

one in which a representative evacuation was modelled along with long term protective actions; and a no evacuation, no long term protective action case. The later case, while unrealistic, provides a very conservative bounding estimate of the consequences. A case with protective actions identical to this study was not reported. However, the results of such an analysis would have provided results intermediate to those reported (with the exception to condemned land which is not affected by emergency response).

Comparison with the results shown in Tables 4.1 and 4.2 clearly indicates that for worst case assumptions, i.e., full pool involvement and large source term, the postulated Configuration 1 spent fuel pool accident may have comparable consequences to a major core melt accident. "

Courtesy of Cryptome.org again we have this little gem of a presentation by Dr. Matthias Braun

A gem indeed, thanks for posting this Dr. Martenson. The graphics are especially helpful for nuclear novices like myself.

Since reactor #4 was offline with all the fuel rods in the pool on 3/11, does this present a greater risk of spreading contamination than a breached core in any of the other reactors?

Mike

Mike -

Short answer is It depends.

Generally speaking, a breached core is far worse because you have lost integrity of the primary coolant containment boundary and the ability to provide cooling water flow to the fuel power unit in the core. A partial meltdown or decomposition of the fuel within the core now has a path to the next level of containment, with the accompanying release of highly radioactive material.

Spent fuel is a different issue since the decay heat generation is likely lower than that of a recently shut down reactor. But you still need water in the spent fuel tanks for both shielding and convective heat removal. As we have seen several times in the Japan accident, the loss of water in the spent fuel pools has resulted in dangerously high radiation levels that have prevented damage control efforts at the other plants. If the water level drops low enough you risk the violent reaction of zircalloy and steam and the rapid oxidation and decomposition of the zirc cladding which will also release significant amounts of radioactive material. This has a potential for a higher impact since the spent fuel is stored outside the primary containment boundary.

Regarding unit #4, I read a report that stated 15% of the fuel assemblies had been removed from the reactor power unit, not all of the fuel. I haven't been able to find corroborating information anywhere, nor a definitive answer on how much sent fuel was already in the storage pools. There have been several reports that said there were 600 tons of spent fuel stored on site, but I haven't found any source that said this was 600 tons per plant or total across all 4.

Thank you, Rocketgirl. I really wish these charts contained an important comparison point: the hourly radiation does from a mid-call cell phone near one's ear.

I found this chart yesterday and while I was looking it over I got a cell phone call from my husband. After talking for about 10 min I decided to switch to speaker and move the phone away from my ear. With the R chart right in front of me I couldn't help but think of the same question. Where does the dose lie for cell phone use? I would love to see something for microwaves too and how about living within 2 miles of a cell phone tower as well as high voltage power lines?(which I think are more electromagnetic). I don't know if they emmit radio activity but I'd like to know the risk. Maybe Dogs can help us. I know there is info on the net but it's hard to know what is legit. Dogs?

"I don't know what made this hole in the roof of the turbine building, but it was heavy."

If something blew up from #3 reactor it would have come down into turbine hall roof, not up through it (two different locations). Normally only the turbines (and maybe control facilities) are in the hall above the top deck (large concrete massively thick floor to take up vibrations and inertia of normal operational forces). Yes the high pressure steam line could have blown up, or the turbine (having been jostled by the earthquake) could have had a seized bearing (they are only slip brearings anyway) and ejected through its housing (not likely). Maybe a valve ejected - but hole too big for that. The most probable thing is that something went Down through the roof from somewhere else (maybe an ejected concrete shield plug). http://en.wikipedia.org/wiki/File:Reaktor.svg

Maybe a boat was washed onto the roof during the tsunami and broke through the roof (they really are not anything but a "built-up" roof of sheet steel, insulation and tar/gravel).

Also if you are looking for something - on the drone aircraft series of pictures - there is a "shadow" of something out in the water just past the intake structure, but inside the breakwater. Looks like something square and about the right size for a reactor shield plug.

Courtesy of Cryptome.org again we have this little gem of a presentation by Dr. Matthias Braun

A gem indeed, thanks for posting this Dr. Martenson. The graphics are especially helpful for nuclear novices like myself.

Since reactor #4 was offline with all the fuel rods in the pool on 3/11, does this present a greater risk of spreading contamination than a breached core in any of the other reactors?

Mike

Mike -

Short answer is It depends.

Generally speaking, a breached core is far worse because you have lost integrity of the primary coolant containment boundary and the ability to provide cooling water flow to the fuel power unit in the core. A partial meltdown or decomposition of the fuel within the core now has a path to the next level of containment, with the accompanying release of highly radioactive material.

Spent fuel is a different issue since the decay heat generation is likely lower than that of a recently shut down reactor. But you still need water in the spent fuel tanks for both shielding and convective heat removal. As we have seen several times in the Japan accident, the loss of water in the spent fuel pools has resulted in dangerously high radiation levels that have prevented damage control efforts at the other plants. If the water level drops low enough you risk the violent reaction of zircalloy and steam and the rapid oxidation and decomposition of the zirc cladding which will also release significant amounts of radioactive material. This has a potential for a higher impact since the spent fuel is stored outside the primary containment boundary.

Regarding unit #4, I read a report that stated 15% of the fuel assemblies had been removed from the reactor power unit, not all of the fuel. I haven't been able to find corroborating information anywhere, nor a definitive answer on how much sent fuel was already in the storage pools. There have been several reports that said there were 600 tons of spent fuel stored on site, but I haven't found any source that said this was 600 tons per plant or total across all 4.

DIAP ~

Thanks so much for taking the time to pen such a thorough answer. I truly appreciate it.

Your statement "this has a potential for a higher impact since the spent fuel is stored outside the primary containment boundary" really helped clear my thinking on this. If I substitute open 5 gal. gas cans for the nuclear fuel rods it seems easy to imagine how much more dangerous they would be (both as an explosive force and as a vapor source) outside of the same containment boundary. (I hope that is a fair analogy.)

Page 30 of the Areva report Dr. Martenson posted has a statement, "due to maintenance in Unit 4 entire core stored in fuel pool". This was my reference for assuming there was no fuel in the core. But I'm certainly no expert, so perhaps my interpretation is not correct.

Have you seen this video commentary by Arnie Gundersen on possible damage to the spend fuel pool at Reactor #4?

Thanks so much for taking the time to pen such a thorough answer. I truly appreciate it.

Your statement "this has a potential for a higher impact since the spent fuel is stored outside the primary containment boundary" really helped clear my thinking on this. If I substitute open 5 gal. gas cans for the nuclear fuel rods it seems easy to imagine how much more dangerous they would be (both as an explosive force and as a vapor source) outside of the same containment boundary. (I hope that is a fair analogy.)

Page 30 of the Areva report Dr. Martenson posted has a statement, "due to maintenance in Unit 4 entire core stored in fuel pool". This was my reference for assuming there was no fuel in the core. But I'm certainly no expert, so perhaps my interpretation is not correct.

Have you seen this video commentary by Arnie Gundersen on possible damage to the spend fuel pool at Reactor #4?

I would be very interested in any comments you might have on his analysis.

Thanks again,

Mike

Mike -

In addition to all of unit #4's fuel being in the pools, there is the question of how much (if any) spent fuel was also stored awaiting reprocessing. The report I read was over a week ago - the Areva data is probably correct.

I have read or watched everything Arnie Gunderson has put out. He is the best source of analysis and information out there IMO. The Fairewinds site is about the only place I go anymore to get my information although I will pulse the standard news sources every now and then - but most of what they are putting out is just a reassembly of other articles or a rehash of what we already know.

I have read or watched everything Arnie Gunderson has put out. He is the best source of analysis and information out there IMO. The Fairewinds site is about the only place I go anymore to get my information although I will pulse the standard news sources every now and then - but most of what they are putting out is just a reassembly of other articles or a rehash of what we already know.

The situation at Fukushima is going to drag on for years.Jct: Our Canadian general election gives us a chance to vote for someone competent to deal with the with the cancer-causing radioactivity to come for the next few years. This is a job for another lawyer. Don't vote for The Engineer, vote yourselves another lawyer to lead us through these dangerous times.Har har har.

"We don't yet know enough to conclude how much fission has spontaneously re-occurred, but we have strong suspicions that the number is higher than zero."

thank you

keith harmon snow

Keith -

Some amount of localized fission events - short lived, but unsustained criticality - has likely occurred as the spent fuel deformed and/or melted. There is always some amount of fissionable fuel left in spent fuel assemblies and it is possible that these particles came into proximity and the correct geometry to allow some degree of fission to occur. The presence of detectable neutron radiation and fission by products confirms that some degree of fission, albeit uncontrolled and short lived, has happened.

Chris and the experts, correct me if I'm wrong, but doesn't continuing episodes of crititcality and the resulting emission of neutrons pose some significant additional hazzards which have not been pointed out so far on this blog (AFAIK)?

- most immediately, the theat to workers on the site. large fluxes of neutrons can destroy blood cells and bone marrow, and they are not easily detected, except by specialized equipment. Normal geiger counters and dossimeters hardly respond at all. People could be getting zapped and not know it.

- continuing production of nasty activation products like I-131, which is supposed to be well on its way to decaying away.

- all other things being equal, chain-reaction fission heat (the main product of a working reactor) is MUCH higher than decay heat of random radioactivity. This could make it much more difficult to bring that damaged reactor under control. Adding water to the situation may very well INCREASE rather than decrease heat output.

- reputable Russian scientists have hypothesized that Chernobyl was in fact a super-low-yield accidental nuclear explosion, rather than just a big chemical hydrogen explosion. People in the nuclear industry always say that things like this are impossible, but at the present out-of-control state of affairs at Fukushima, it may not be beyond the realm of possibility.

Superimposing the night shot with one from the daylight, we see that the light is coming from the port.. so it's most likely the workers working overtime on the leak(s), and they use a spotlight from a boat or something

So just reading through all the reports coming in, it now appears almost certain that:

1) nuclear fuel has been damaged / melted and high-level radioactive material is leaking out of the fuel rods into the reactor coolant.

2) The reactor coolant circuits (RPV + primary piping) are leaking in at least one and possible more than one reactors (note the lack of pressure in units #2 and #3 RPV's for example as compared to #1).

3) The primary containment vessel is leaking in at least one of the reactors, most likely in #2 (probably from an explosion in / around the suppression pool).

So all three layers of containment appeared to have failed in at least one of the reactors. This is a gross failure of design and/or accident management. And, although the public health effects still MAY be minimum, it's is definitely a more serious and significant event than the TEPCO and Japanese authorities are publicly acknowledging.

Now on top of this, they are continuing to pump large quantities of fresh water INTO the RPV's. So we now have an open circuit where fresh water is being pumped into the RPV, collects radioactive debris from the damaged fuel, and finds it way out of the reactor coolant circuit, out of the primary containment and ultimately outside of the reactor building. So until they find a way of "closing this circuit" and recirculating the contaminated water (rather than just injecting more water), they are going to continue to accumulate large quantities of highly contaminated water. It brings into question what are they going to do with all this highly contaminated water once they fill up the waste treatment facilities' storage tanks again.

Chris and the experts, correct me if I'm wrong, but doesn't continuing episodes of crititcality and the resulting emission of neutrons pose some significant additional hazzards which have not been pointed out so far on this blog (AFAIK)?

- most immediately, the theat to workers on the site. large fluxes of neutrons can destroy blood cells and bone marrow, and they are not easily detected, except by specialized equipment. Normal geiger counters and dossimeters hardly respond at all. People could be getting zapped and not know it.

- continuing production of nasty activation products like I-131, which is supposed to be well on its way to decaying away.

- all other things being equal, chain-reaction fission heat (the main product of a working reactor) is MUCH higher than decay heat of random radioactivity. This could make it much more difficult to bring that damaged reactor under control. Adding water to the situation may very well INCREASE rather than decrease heat output.

- reputable Russian scientists have hypothesized that Chernobyl was in fact a super-low-yield accidental nuclear explosion, rather than just a big chemical hydrogen explosion. People in the nuclear industry always say that things like this are impossible, but at the present out-of-control state of affairs at Fukushima, it may not be beyond the realm of possibility.

Hello Robert -

Rest assured that whatever degree of localized criticality is occurring, the emergency response workers are aware of it. Neutron detection equipment is standard gear routinely used for periodic shield and boundary surveys during plant operations. The tricky part is managing response when they do detect neutron radiation. It's most likely coming from these critical "hot spots" and my guess is the workers drop back to a distance where the radiation level is manageable and they wait for the fission event to end. Because neutrons are so heavy, the amount of biological damage they do is large compared to the other types of radiation - this is compounded by the fact that it is difficult to shield neutron radiation.

The presence of I-131 this many days after shutdown all but confirms that some degree of these localized fission events are/were occurring. I-131 can also be released from the zircalloy fuel matrix in the spent fuel assemblies as they break down, blister and crack.

It's not so much that the heat produced by normal, sustained fission is "hotter" per se, it's just that a normal fission reaction has a lot more neutron production, absorption and ejection going on so the rate of heat production is what is the driver here. Adding water to a shutdown reactor isn't going to increase the heat output and you need the water's moderation of fast neutrons to thermal energies for normal critical operations.

Chernobyl WAS NOT a super low-yield nuclear detonation. It was a fire involving highly radioactive material. Even the most highly enriched nuclear fuel for power plant operations pales in comparison to the degree of enrichment for weapons grade uranium/plutonium. You also need a host of other materials, supporting subsystems and components for a NUDET. The mechanisms for releasing the energy are very different and the geometry of nuclear fuel for a power plant can't conceivably be rearranged in such a manner as to cause a fusion "trigger" igniting a primary or the old gun tube type weapons where a highly enriched ball of weapons grade material is fired at high speed into another highly enriched ball of weapons grade material with a subsequent release and cascade of fast neutron generations above supercritical levels. Such a scenario at Fukushima Daiichi is for all intents and purposes, beyond the realm of possibility - perhaps not an absolute zero chance, but about as close to zero as you can get.

You wrote: "I-131 can also be released from the zircalloy fuel matrix in the spent fuel assemblies as they break down, blister and crack." Why would there be any I-131 left in the spent fuel assemblies? Shouldn't most of this have decayed away by now? The spent fuel assemblies have been out of a operating reactor for at least several weeks, so there shouldn't be much I-131 left in them.

Also, I thought the accident at Chernobyl was indeed caused by a nuclear transient, compounded by the poor design of the graphite-tipped control rods that actually increased the nuclear reactivity instantaneously when originally inserted. True, this isn't comparable to a nuclear explosion in a weapon, but nonetheless there was in fact a nuclear power transient that caused damage to the reactor at Chernobyl and led to the subsequent fire.

Unboronated water could in fact increase the local "hot-spot" reactivity in portions of the Daichi cores, depending on the geometry of the debris. However, I believe they are adding boron into the water as its injected.

I agree there is no chance of a "weapons-grade" nuclear explosion, but any fission occurring at this point only exacerbates the situation.

You wrote: "I-131 can also be released from the zircalloy fuel matrix in the spent fuel assemblies as they break down, blister and crack." Why would there be any I-131 left in the spent fuel assemblies? Shouldn't most of this have decayed away by now? The spent fuel assemblies have been out of a operating reactor for at least several weeks, so there shouldn't be much I-131 left in them.

If there was localized fission occurring in the spent fuel as a result of deformation, I-131 would be produced. Thankfully at very low levels. The fact that I-131 is being detected confirms localized fission events in either the spent fuel or in the core or both. Or the information being released about the isotopes being detected is incorrect.

Quote:

Also, I thought the accident at Chernobyl was indeed caused by a nuclear transient, compounded by the poor design of the graphite-tipped control rods that actually increased the nuclear reactivity instantaneously when originally inserted. True, this isn't comparable to a nuclear explosion in a weapon, but nonetheless there was in fact a nuclear power transient that caused damage to the reactor at Chernobyl and led to the subsequent fire.

Chernobyl was the result of an exquisitely poorly planned and executed drill. The design of the control rods wasn't poor per se, but when they were inserted, they displaced water which normally acts as a neutron absorber to limit core power. The rods functioned exactly as they were intended to and the plant responded exactly as it should have. The problem was the plant and core power conditions were so far out of normal parameters that the resulting power excursion was uncontrollable. The plant was never designed to operate under the conditions the operators established - and from a strictly theoretical standpoint, the plant responded as it should have.

Unboronated water could in fact increase the local "hot-spot" reactivity in portions of the Daichi cores, depending on the geometry of the debris. However, I believe they are adding boron into the water as its injected.

I agree there is no chance of a "weapons-grade" nuclear explosion, but any fission occurring at this point only exacerbates the situation.

Whether or not there is potassium tetraborate in the water is of little concern. Any localized fission that is compounded by the presence of water that acts as a moderator is an acceptable consequence of addressing the most pressing concern - decay heat removal.

The accident as it is is like getting hit in the face with a 7 pound maul. Adding the dynamic of localized criticality makes it like getting hit in the face with a 10 pound maul. Given a choice you'd take the 7 pound maul, but what's the difference?

"resulting power excursion was uncontrollable" This sounds like a nuclear power transient to me. Not just a chemical fire.

"The accident as it is is like getting hit in the face with a 7 pound maul. Adding the dynamic of localized criticality makes it like getting hit in the face with a 10 pound maul. Given a choice you'd take the 7 pound maul, but what's the difference?"

The difference is you now have fresh, short-half-life isotopes being generated in a clad-damaged, containment-breached reactor. This posses additional radiological hazard, should significant quantities of I-131 get released into the air again.

By the way, interesting article in the NY Times indicates additional matters of concern: